Astronomers have found eight new planets orbiting in the “Goldilocks Zone,” around their stars, that area where conditions are “just right” to support liquid water and maybe life. Two of the planets found are the most Earth-like ever discovered.
“Most of these planets have a good chance of being rocky, like Earth,” said study lead author Guillermo Torres of the Harvard-Smithsonian Center for Astrophysics (CfA).
The most earth-like planets, Kepler-438b and Kepler-442b, both orbit red dwarf stars that are smaller and cooler than the sun.
Kepler-438b, 470 light-years from Earth, is just 12 percent bigger than the Earth and has a 70 percent chance of being rocky. It orbits its star every 35 days. It gets about 40 percent more sunlight than the earth, which gives it a 70 percent chance of being in the habitable zone around its star, according to the study.
Kepler-442b, 1,100 light-years from Earth, is about a third larger than the earth and has a 60 percent chance of being rocky. It makes an orbit every 112 days. It gets two-thirds as much light as the Earth, giving it a whopping 97 percent chance of being in the habitable zone.
The eight new discoveries double the number of planets less than twice the diameter of Earth found in habitable zones. But astronomers cautioned being in the right place doesn’t necessarily mean we’ll find life or the conditions to support life there.
“We don’t know for sure whether any of the planets in our sample are truly habitable,” explains second author David Kipping of the CfA. “All we can say is that they’re promising candidates.”
Artist’s conception of an exoplanet by David A. Aguilar (CfA)